Engage the reader immediately with a positive tone and exciting verbiage. An exciting phrase will get the reader to click the link or buy the book.
Present the benefit of your product, clearly. Tell the customer how your product will entertain him or make her more productive. Also, spell out who will benefit from the product. A product for housewives should not be marketed to Fortune 500 CEOs.
Present the information in a concise format that lists the name of your product, a descriptive adjective, the genre in which you plan to market, who will benefit most and the key benefit he will receive from using the product. This entire blurb should take no more than two sentences.